(function () {
	cc.isUndefined = function (arg) {
		return arg === void 0;
	};

	cc.isObject = function (arg) {
		return typeof arg === "object" && arg !== null;
	};

	cc.isFunction = function (arg) {
		return typeof arg === "function";
	};

	cc.isTimestamp = function (arg) {
		return cc.isNumber(arg) && new Date(arg * 1000).getFullYear() != 1970;
	};

	function EventEmitter(maxListeners) {
		this._events = this._events || {};
		this._maxListeners = maxListeners || undefined;
	}

	//  Backwards-compat with node 0.10.x
	EventEmitter.EventEmitter = EventEmitter;

	EventEmitter.prototype._events = undefined;
	EventEmitter.prototype._maxListeners = undefined;

	//  By default EventEmitters will print a warning if more than 10 listeners are
	//  added to it. This is a useful default which helps finding memory leaks.
	EventEmitter.defaultMaxListeners = 10;

	//  Obviously not all Emitters should be limited to 10. This function allows
	//  that to be increased. Set to zero for unlimited.
	EventEmitter.prototype.setMaxListeners = function (n) {
		if (isNaN(n) || n < 0) throw TypeError("n must be a positive number");
		this._maxListeners = n;
		return this;
	};

	EventEmitter.prototype.emit = function (type) {
		var er, handler, len, args, i, listeners;

		if (!this._events) this._events = {};

		// If there is no 'error' event listener then throw.
		if (type === "error" && !this._events.error) {
			er = arguments[1];
			if (er instanceof Error) {
				throw er; // Unhandled 'error' event
			} else {
				throw Error('Uncaught, unspecified "error" event.');
			}
			return false;
		}

		handler = this._events[type];

		if (cc.isUndefined(handler)) return false;

		if (cc.isFunction(handler)) {
			var __caller = handler.__caller || this;
			switch (arguments.length) {
				// fast cases
				case 1:
					handler.call(__caller);
					break;
				case 2:
					handler.call(__caller, arguments[1]);
					break;
				case 3:
					handler.call(__caller, arguments[1], arguments[2]);
					break;
				// slower
				default:
					len = arguments.length;
					args = new Array(len - 1);
					for (i = 1; i < len; i++) args[i - 1] = arguments[i];
					handler.apply(__caller, args);
			}
		} else if (cc.isObject(handler)) {
			len = arguments.length;
			args = new Array(len - 1);
			for (i = 1; i < len; i++) args[i - 1] = arguments[i];

			listeners = handler.slice();
			len = listeners.length;
			for (i = 0; i < len; i++) {
				var __caller = listeners[i].__caller || this;
				listeners[i].apply(__caller, args);
			}
		}

		return true;
	};

	EventEmitter.prototype.addListener = function (type, listener, caller) {
		var m;

		if (!cc.isFunction(listener))
			throw TypeError("listener must be a function");

		listener.__caller = caller;

		if (!this._events) this._events = {};

		// To avoid recursion in the case that type === "newListener"! Before
		// adding it to the listeners, first emit "newListener".
		if (this._events.newListener)
			this.emit(
				"newListener",
				type,
				cc.isFunction(listener.listener) ? listener.listener : listener
			);

		if (!this._events[type])
			// Optimize the case of one listener. Don't need the extra array object.
			this._events[type] = listener;
		else if (cc.isObject(this._events[type]))
			// If we've already got an array, just append.
			this._events[type].push(listener);
		// Adding the second element, need to change to array.
		else this._events[type] = [this._events[type], listener];

		// Check for listener leak
		if (cc.isObject(this._events[type]) && !this._events[type].warned) {
			var m;
			if (!cc.isUndefined(this._maxListeners)) {
				m = this._maxListeners;
			} else {
				m = EventEmitter.defaultMaxListeners;
			}

			if (m && m > 0 && this._events[type].length > m) {
				this._events[type].warned = true;
				console.error(
					"(node) warning: possible EventEmitter memory " +
						"leak detected. %d listeners added. " +
						"Use emitter.setMaxListeners() to increase limit.",
					this._events[type].length
				);
				console.trace();
			}
		}

		return this;
	};

	EventEmitter.prototype.on = EventEmitter.prototype.addListener;

	EventEmitter.prototype.once = function (type, listener, caller) {
		if (!cc.isFunction(listener))
			throw TypeError("listener must be a function");

		var fired = false;
		var that = this;
		function g() {
			that.removeListener(type, g);

			if (!fired) {
				fired = true;
				listener.apply(caller || that, arguments);
			}
		}

		g.listener = listener;
		this.on(type, g, caller);

		return this;
	};

	EventEmitter.prototype.onnp = function (type, listener, key) {
		if (!cc.isFunction(listener))
			throw TypeError("listener must be a function");
		if (!this._noRepeatKey) this._noRepeatKey = {};

		var _key = key;
		if (_key == null) _key = type + "_" + listener.toString();

		if (this._noRepeatKey[_key]) {
			this.removeListener(type, this._noRepeatKey[_key]);
		}
		this._noRepeatKey[_key] = listener;
		this.on(type, listener);
		return this;
	};

	//  emits a 'removeListener' event iff the listener was removed
	EventEmitter.prototype.removeListener = EventEmitter.prototype.off =
		function (type, listener) {
			var list, position, length, i;

			if (!cc.isFunction(listener)) {
				throw TypeError("listener must be a function");
				//return this;
			}

			if (!this._events || !this._events[type]) return this;

			list = this._events[type];
			length = list.length;
			position = -1;

			if (
				list === listener ||
				(cc.isFunction(list.listener) && list.listener === listener)
			) {
				delete this._events[type];
				if (this._events.removeListener)
					this.emit("removeListener", type, listener);
			} else if (cc.isObject(list)) {
				for (i = length; i-- > 0; ) {
					if (
						list[i] === listener ||
						(list[i].listener && list[i].listener === listener)
					) {
						position = i;
						break;
					}
				}

				if (position < 0) return this;

				if (list.length === 1) {
					list.length = 0;
					delete this._events[type];
				} else {
					list.splice(position, 1);
				}

				if (this._events.removeListener)
					this.emit("removeListener", type, listener);
			}

			return this;
		};

	EventEmitter.prototype.removeAllListeners = function (type) {
		var key, listeners;

		if (!this._events) return this;

		// not listening for removeListener, no need to emit
		if (!this._events.removeListener) {
			if (arguments.length === 0) this._events = {};
			else if (this._events[type]) delete this._events[type];
			return this;
		}

		// emit removeListener for all listeners on all events
		if (arguments.length === 0) {
			for (key in this._events) {
				if (key === "removeListener") continue;
				this.removeAllListeners(key);
			}
			this.removeAllListeners("removeListener");
			this._events = {};
			return this;
		}

		listeners = this._events[type];

		if (cc.isFunction(listeners)) {
			this.removeListener(type, listeners);
		} else if (Array.isArray(listeners)) {
			// LIFO order
			while (listeners.length)
				this.removeListener(type, listeners[listeners.length - 1]);
		}
		delete this._events[type];
		this._noRepeatKey = {};

		return this;
	};

	EventEmitter.prototype.listeners = function (type) {
		var ret;
		if (!this._events || !this._events[type]) ret = [];
		else if (cc.isFunction(this._events[type])) ret = [this._events[type]];
		else ret = this._events[type].slice();
		return ret;
	};

	EventEmitter.listenerCount = function (emitter, type) {
		var ret;
		if (!emitter._events || !emitter._events[type]) ret = 0;
		else if (cc.isFunction(emitter._events[type])) ret = 1;
		else ret = emitter._events[type].length;
		return ret;
	};

	cc.EventEmitter = new EventEmitter(8);
	cc.EventEmitter.create = function (maxListeners) {
		return new EventEmitter(maxListeners);
	};
})();
